Generation of Environmental Raster Data
EZD Team
20 May 2019
1 Raster Data
1.1 Raster for Bavaria
- Extract Bavaria Shape from Spatial Germany
ger_file <- getData("GADM", country = "Germany", level = 1)
bay_file <- ger_file[match(toupper("Bayern"),toupper(ger_file$NAME_1)),]- Create a Random Raster Over the Space
bay_raster <- raster(xmn = 8.975, xmx = 13.84167, ymn = 47.26667, ymx = 50.56667, nrow = 396, ncol = 584)
bay_raster[] <- runif(396*584)- Create Mask
bay_mask <- mask(bay_raster, bay_file)1.2 Data Acquisition
1.2.1 Height
- Load Data
height <- getData(name = "alt", country = "Germany")- Change Layer Name
names(height) <- "height"- Cut Bavaria Shape
height <- crop(height, bay_mask)
height <- mask(height, bay_mask)- Save Raster
writeRaster(height, "../../Daten/Raster/height_raster")1.2.2 Temperature and Rain
- Load Data
weatherdata <- getData("worldclim", var = "bio", res = 0.5, lon = 12.101624, lat = 49.013432)
weatherdata <- weatherdata[[c(1, 12)]]- Change Name
names(weatherdata) <- c("temp", "rain")- Cut Bavaria Shape
weatherdata <- crop(weatherdata, bay_mask)
weatherdata <- mask(weatherdata, bay_mask)
weatherdata <- stack(weatherdata[[1]] / 10, weatherdata[[2]])- Save Raster
writeRaster(weatherdata[[1]], "../../Daten/Raster/temp_raster")
writeRaster(weatherdata[[2]], "../../Daten/Raster/rain_raster")1.2.3 Slope, Aspect, Tpi
- Load Data
env_data <- terrain(height, opt = c("slope", "aspect", "tpi"), unit = "degrees")- Turn into Cathegorial Variable
env_data$aspect <- ceiling((env_data$aspect + 360/8/2)/(360/8))
env_data$aspect[env_data$aspect > 8] <- 1- Cut Bavaria Shape
env_data <- crop(env_data, bay_mask)
env_data <- mask(env_data, bay_mask)- Save Raster
writeRaster(env_data[[1]], "../../Daten/Raster/tpi_raster")
writeRaster(env_data[[2]], "../../Daten/Raster/slope_raster")
writeRaster(env_data[[3]], "../../Daten/Raster/aspect_raster")1.2.4 Water Distance
(Source: s. Bene)
- Load Shapefiles
river_shape <- shapefile("../../Daten/Raster/RawFiles/DEU_water_lines_dcw.shx")
lake_shape <- shapefile("../../Daten/Raster/RawFiles/DEU_water_areas_dcw.shx")- Create Water Rasters
river_raster <- mask(bay_raster, river_shape)
lake_raster <- mask(bay_raster, lake_shape)- Calculate Distance to Rivers and Lakes
distance_river <- distance(river_raster)
distance_lake <- distance(lake_raster)- Minimum of Distance to Rivers and Distance to Lakes is Distance to Water
distance_water <- min(distance_lake, distance_river)- Save Raster Files
writeRaster(distance_river, "../../Daten/Raster/RawFiles/river")
writeRaster(distance_lake, "../../Daten/Raster/RawFiles/lake")
writeRaster(distance_water, "../../Daten/Raster/RawFiles/water")- Change Name
names(distance_water) <- "distance_water"- Cut Bavaria Shape
distance_water <- mask(distance_water, bay_mask)- Save Raster
writeRaster(distance_water, "../../Daten/Raster/distance_water_raster")1.2.5 Loess Distance
(Source: https://www.lfu.bayern.de/umweltdaten/geodatendienste/pretty_downloaddienst.htm?dld=gk500)
- Load Shapefiles
loess_shape <- shapefile("../../Daten/Raster/RawFiles/Loess/gk500_haupteinheiten_epsg4258.shx")
# Warum Haupteinheiten? Was ist mit Linien, Struktur? Enthält Haupteinheiten alles?- Subsetting for Loess
loess_shape <- loess_shape[str_detect(loess_shape$kurztext, "Löß"),]- Create Loess Raster
loess_raster <- mask(bay_raster, loess_shape)- Calculate Distance to Loess Sediments
distance_loess <- raster::distance(loess_raster)- Change Name
names(distance_loess) <- "distance_loess"- Save Raster File
writeRaster(distance_loess, "../../Daten/Raster/RawFiles/loess")- Cut Bavaria Shape
distance_loess <- mask(distance_loess, bay_mask)- Save Final Raster
writeRaster(distance_loess, "../../Daten/Raster/distance_loess_raster")1.2.6 Frostdays
(Source: https://maps.dwd.de/geoserver/web/wicket/bookmarkable/org.geoserver.web.demo.MapPreviewPage?0)
- Import Data
frostdays <- raster("../../Daten/Raster/RawFiles/dwd-Frostdays_annual_map_normals_1971_30.tif")- Change Name
names(frostdays) <- "frostdays"- Change Coordinates to WGS
frostdays <- projectRaster(frostdays, crs = crs(bay_mask))- Data in Bavaria Shape
frostdays <- resample(frostdays, bay_mask)
frostdays <- mask(frostdays, bay_mask)- Save Final Raster
writeRaster(frostdays, "../../Daten/Raster/frostdays_raster")- Load Final Raster
# frostdays <- raster("../../Daten/Raster/frostdays_raster.grd")1.2.7 Sunhours
(Source: https://maps.dwd.de/geoserver/web/wicket/bookmarkable/org.geoserver.web.demo.MapPreviewPage?0)
- Import Data
sunhours <- raster("../../Daten/Raster/RawFiles/dwd-SDMS_17_1971_30.tif")- Change Name
names(sunhours) <- "sunhours"- Change Coordinates to WGS
sunhours <- projectRaster(sunhours, crs = crs(bay_mask))- Data in Bavaria Shape
sunhours <- resample(sunhours, bay_mask)
sunhours <- mask(sunhours, bay_mask)- Save Final Raster
writeRaster(sunhours, "../../Daten/Raster/sunhours_raster")- Load Final Raster
# sunhours <- raster("../../Daten/Raster/sunhours_raster.grd")1.2.8 Corine
(Source: https://land.copernicus.eu/pan-european/corine-land-cover/clc2018?tab=download)
- Import Data
corine <- raster("../../Daten/Raster/RawFiles/CLC2012_CLC2006_V2018_20b2.tif")- Change Name
names(corine) <- "corine"- Change Coordinates to WGS
corine <- projectRaster(corine, bay_mask)- Save Raster File
writeRaster(corine, "../../Daten/Raster/RawFiles/corine")- Data in Bavaria Shape
corine <- mask(corine, bay_mask)- Save Final Raster
writeRaster(corine, "../../Daten/Raster/corine_raster")1.3 Stack File with Raster Data
- Load all Predictors
predictors <- stack(c(
"../../Daten/Raster/height_raster.grd",
"../../Daten/Raster/temp_raster.grd",
"../../Daten/Raster/rain_raster.grd",
"../../Daten/Raster/distance_water_raster.grd",
"../../Daten/Raster/distance_loess_raster.grd",
"../../Daten/Raster/frostdays_raster.grd",
"../../Daten/Raster/sunhours_raster.grd",
"../../Daten/Raster/corine_raster.grd",
"../../Daten/Raster/tpi_raster.grd",
"../../Daten/Raster/slope_raster.grd",
"../../Daten/Raster/aspect_raster.grd"))- Transformed Stack
predictors <- stack(c(
predictors[[1]]/100,
predictors[[2]],
predictors[[3]],
predictors[[4]]/1000,
predictors[[5]]/1000,
predictors[[6]],
predictors[[7]],
predictors[[8]],
predictors[[9]],
predictors[[10]],
predictors[[11]]
))- Plot Rasters
plot(predictors[[1]], main = "height")
plot(predictors[[2]], main = "temp")
plot(predictors[[3]], main = "rain")
plot(predictors[[4]], main = "distance_water")
plot(predictors[[5]], main = "distance_loess")
plot(predictors[[6]], main = "frostdays")
plot(predictors[[7]], main = "sunhours")
plot(predictors[[8]], main = "corine")
plot(predictors[[9]], main = "tpi")
plot(predictors[[10]], main = "slope")
plot(predictors[[11]], main = "aspect")